Refrigerated container



Sept. 16, 1941. c c 2,256,110

REERIGERATED CONTAINER Filed March 9, 1959 5 Sheets-Sheet l .ZemrQ/FGZera -53 Sept. 16, 1941. F. cLERc REFRIGERATED CONTAINER Filed March 9, 1959 5 Sheets-Sheet 2 Sept. 16, 1941. F. CLERC REFRIGERATED CONTAINER Filed March 9, 1939 5 Sheets-Sheet 3 [salad/ 620 c p 1 1941- F. CLERC REFRIGERATED CONTAINER Filed March 9, 1939 5 Sheets-Sheet 4 Sept. 1941@ F. CLERC REFRIGERATED CONTAINER 5 Sheets-Sheet 5 Filed March 9, 1959 tainer, with the doors in open position:

Patented Sept. 16, 1941 UNITED STATES PATENT OFFICE 2,256,110 nsrmosna'rnn CONTAINER Leonard F. Clerc, Chicago, Ill;

Application March 9, 1939, Serial No. 260,703 (o1. sa -91.5)

1 Claims.

My invention relates generally to refrigerated containers, and more particularly to improve ments in compact shipping containers for use in the shipment of frozen foods and other foods or products which it is desired to maintain at a relatively low temperature. I

It is an object of my invention to provide an improved refrigerated shipping container which is compact, may be easily handled, and has provisions for refrigerating its contents by means of dry ice, or other refrigerant.

A further object is to provide a refrigerated shipping container which-may conveniently be used as a cabinet by the consignee, and may thus be used to maintain its contents at a low temperature until they are sold. Thus, a retail grocery store may'utilize the container as a temporary refrigerator for the storage of the food products until they are sold, and then upon the delivery of a filled container, return the 'empty one, in this manner facilitating the shipment and storage of the food," and the return of the empty containers. 7 v

A further object is to provide an improved refrigerated container in which adequate circulation of air in the container is readily maintained, thereby to insure that even if the container is packed full .of packaged food products, the contents will be maintained at the requisite low temperature.

A further object is to provide a refrigerated container which may conveniently be used with ice or dry ice as the refrigerating medium, or which may be connected to a mechanical refrigcrating unit.

A further object is to provide an improved refrigerated cabinet which may conveniently be connected to the evaporator circuit of a mechanical refrigerating unit, enabling the container to be used as a subscriber's locker ina cold storage.-

plant. Other objects panying drawings, in which:

Figure 1 is a front elevational view of the conwill appear from the following description; reference being had to the accom- Figure 6 is an enlarged fragmentary sectional view taken in a plane perpendicular'to that of Figure 5;

Figure '7 is a horizontal sectional view taken on the line |--l of Figure 6;

Figure 8 is a fragmentary vertical sectional view of a modified form of the invention, in

which the container is connected to amechanical refrigerating system;

Figure 9 is a fragmentary sectional view of a second modified form of theinventiori; and,

Figure 10 is a fragmentary vertical sectional view of a third modified form of the invention.

In the past, considerable difficulty has been experienced in the transportation of refrigerated and frozen foods, due to the difiiculty of maintaining the food products atthe necessary low temperature throughout transit from the packer to the retail establishment selling the products. For the supply of such food products to larger cities, the problem has been solved in a measure by shipping the food products in refrigerated freight cars and unloading them directly into'a cold storage warehousing plant. In some in stances, refrigerated trucks have been utilized to transport the food products from the cold storage warehouses to the retail stores. In the smaller cities, however, the consumption of frozen and be shipped in the manner of other food products,

since the container is thoroughly insulated, and is provided with a self-contained refrigerating means, whereby the food in the container may be maintainedat the requisite low temperature throughout transitfrom the packer to the retailer. The containers are of a size approximating tainer, with the-doors thereof in closed position;

Figure 2 is a front elevational view of the conview of the top portion ofthe container, showing particularly the dry ice compartment;

that of a large trunk, so that they may be conveniently handled by a single man in loading them. in the freight cars, and unloading them from the freight cars on to trucks. They are made sufliciently light in weight so as not to add excessive tare to the weight of the shipment, are

made very durable so as to withstand the rough handling to which they are subjected, and are so I simple in construction, and employ such a simple method of refrigeration that they may be serviced by relatively unskilled help.

Exemplary forms of my invention are shown in the drawings, the forms shown in Figs. 1 to 7, inclusive, comprising a metal shell forming an outer box 28, the walls 22 of which are preferably corrugated to increase their rigidity, the walls being joined at their edges by rigid angles 24, preferably by welding. The front panel 26 is provided with openings which are closed by hinged doors 28 and 38, the door 28 providing access to the food product compartment 32, while the door 38 provides access to the refrigerating compartment 34. The compartments 32 and 34 are formed by welded corrugated sheets 36, the corrugations in the vertical walls thereof extending vertically to provide a space for the circulation of air about the contents of the container.

As best shown in Figs. and 6, a tank-like housing 38 is supported on projections 38 which may be stamped from, or welded to, the side walls 36, and is further held in position by abutment of lugs 4| which may be welded to the top of the housing 38 .and abut the top wall of the inner case. The housing 38 is formed of pressed metal corrugated sheets which are welded together. The open end of the housing 38 has a frame 48 welded thereto, the frame being drilled and tapped at suitable intervals to receive cap screws 42, which a cover 44 is.

to a pressure regulating. valve 56 from which the carbon' dioxide flows through a serpentine coil '58 through a manually operated pressure control valve 68 and a vent duct 62 to the atmosphere. The coil 58 is secured by clips or the like to a plate 64, which, in turn, is secured by Z-shaped-bars 66 with the housing 38. The spaces between the Z-shaped bars 66 form passageways for the circulation of air between the bottom of the housing 38 and the plate I 64. These passageways are open at their ends, and thus provide paths for the circulation of air,

and thereby facilitate maintaining the contents of the container at a low temperature. It will be noted that the housing 38 is spaced slightly from the walls 36 of the chamber 34, so that its entire exterior surface may be contacted by the air within the container.

. The pressure regulating valve 56 is preferably offlthe adjustable spring loaded type, and may be set to permit venting of the carbon dioxide in the housing 38 to the atmosphere whenever the pressure in the housing exceeds a predetermined value, such as ten or fifteen pounds pefsquare inch. By maintaining the carbon dioxide in the housing 38 under pressure,

the rate of evaporation may be reduced thereby to maintain the food products in the container at the desired low pressure without theinefliciency inherent when the. dry ice is permitted.

to evaporate freely and thus lower the temperature of the contents "of the container below a value necessary to, maintain the products in good condition.

- The connection between the vent pipe 62 and ceiving seals 88.

valve 68, whereupon the assembly, consisting of the casing 38 and all parts secured thereto, may be removed from the container as a unit. Convenient means may be provided to lock the casing rigidly in position, as determined by the brackets 38 and lugs 4|. Thus, if it should become necessary to repair or replace the dry ice receiving casing 38, it may be removed for such repair, and a similar unit substituted therefor, making it unnecessary to keep the entire container out of service during the time consumed in making such repairs.

The top of the container is provided with a handle 18 which is welded or otherwise suitably secured to the top of the container, so that the container may be easily tipped so as to rest upon a pair of rollers 12, which are secured to the side of the container adjacent the bottom thereof, by suitable bearing brackets I4 which may be welded or riveted to the angle iron 24 whichextends along the side bottom edge of the container.

The door 38 is provided with a suitable shipping tag holder 16, which may be of any suitable form to receive the shipping labels or 7 tags.

The doors 28 and 38 are provided with suitable locking means to hold them securely in closed position, such locking means being illustrated as simple latches vI8, these locking means being preferably of a type which has means for re- The flanges of the doors are provided with rubber gaskets 82, so as to make the container substantially air tight.

The door jambs are lined with strips 84 of heat insulating material, such as Bakelite. The inner case formed by the ribbed or corrugated sheets 36 is spaced from the outer housing formed by the sheets and panels 26 by suitable struts or spacers 86, and the space between the inner case and outer housing is filled with suitable heat insulating material 88. The doors 28 and 38 are likewise filled with a heat insulating material. The material is packed in tightly so as to'form a cushioning backing for the sheets 26 forming the outer walls of the container.

In using the container, the products to be shipped, having preferably been pre-cooled, are placed in the compartment 32 and may be packed in to this compartment tightly, because adequate circulation of cooling air about the products is assured by virtue of the spaces between the ribs or corrugations formed on the inside walls 36 of the. compartment. Depending upon the expected time that the containr will be in transit, the casing 38 may be filled or partially filled with dry ice. The casing 38 is then sealed by securely clamping the cover door 44 over the end opening thereof. Upon opening the valve 68, the doors 28 and 38 may be closed and sealed,

whereupon the container will be in condition for shipment. During transit, the dry ice will, of course, evaporate at a rate determined in part byithb setting of the pressure relief valve 56, and due to theciggulation of air in the container around thecasing .38, as well as through the passageways formed-{between the Z-shaped bars 66, the food or other product within the container will be maintained at any predetermined low temperature. The carbon dioxide gas evaporating from the dry ice is, of course, caused the valve 68 is an ordinary threaded connection,

so that the vent pipe may be unscrewed from the to flow through the coil 58, and during the course of such flow expands, thus increasing. its refrigcrating properties so that a maximum amount of heat will be carried from the container.

Upon receipt of the container, the consignee, upon opening the door 88, may note the reading of the gauge 58, and if pressure is still maintained in the casing 38, he is assured that the shipment has been maintained at the required low temperature throughout transit. therefore use the container as a temporary refrigerator, and remove the contents as they are sold, replenishing the dry ice in the casing 38 only when the need is indicated by the drop in the pressure within the casing 88, as shown by the gauge 58. If it is not necessary to keep .the contents at a very low temperature, the consignee may place ice in the casing 38, being,

however, careful to drain the casing after the ice has melted. Whenever it is necessary to open the cover door 88 while the pressure within the casing 38 is still above atmospheric pressure, it is desirable to vent the casing by opening the valve -52 prior to unscrewing the cap screws 82, and thus prevent possible damage to the sealing gasket 88.

In Fig. 8, I have shown a modified form of my 'invention wherein the container is adapted to be connected to an external source of a refrigerating medium. This type of installation may conveniently be used in food storage locker plants.

The container proper may be of the same con- He may;

struction as shown in Figs. 1 to 7, inclusive, with l the exception of the refrigerating unit installed therein. In Fig. 8, the refrigerating unit comprises a tank I88, which is generally rectangular in both vertical and horizontal cross section, and

has a plurality of depending ribs I82 formed in the bottom surface thereof to provide passageways I88 for the circulation of air. The tank is preferably filled with a suitable liquid having a low freezing point, such as alcohol or brine, the tank being filled through a-fiilingpipe I88 normally closed by a plug I88. .The tank I88 may be drained through a similar drain pipe 8, which is normally closed by a pipe plug II2. Within the tank I88 is a compartment II8, one end of which is open and extends through an opening formed in the front end of the tank I88, the opening being normally. closed by a suitable door. The compartment II8 is available for freezing food products, and is surrounded by a coil H8, the ends of which are connected to conduits H8 and I28.

frigerating medium. The coil H8 may thus be a portion of the evaporator coil system of a mechanical refrigerating unit, and in this event a suitable expansion valve will be provided to con- These conduits supply to and carry away-from the coil II8 a suitable retrol the flow of the refrigerating medium into the coil II8. In other installations where a brine circulating system is used, the conduit 8 may be'connected to the'pressure side of the brine circulating system, while the conduit I28 forms the return. a

With containers shown in Fig. 8, a locker storage plant may be constructed in which the subscribers, or owners of the plant, may have access to the stored food owned by them without having to go into a chilled or cooled room. Furthermore, the food within the container is substantially sealed, so that it is unnecessary to take the usual precautions to prevent excess evaporation of moisture from the food.

The modified form of my invention shown in Fig. 9 is likewise adapted foruse in locker storage plants or other places where the container may be connected to a suitable supply of a re- I frigerating medium. In this construction, the container is provided with a coil I22 which surrounds a casing I28 divided into passageways by plates I28 and I28. The conduit forming the,

of may constitute an expansion coil of a refrigerating apparatus, or may have brine or other cold fluid or liquid circulated therethrough.

In the modification shown in Fig. 10, there is provided a casing I32 which has welded thereto at the bottom a tank I38 containing alcohol. or other liquid having a low freezing point. In this construction, the casing I82 is adapted to be filled or partially filled with dry ice, while the tank I38 and the alcohol or other liquid contained therein forms a heat conducting means,as well as a heat reservoir. The tank I88 may be filled and drained through pipes I38 and I88, respectively, which are normally closed by suitable pipe plugs or caps. The type of dry ice containing casing shown in Fig. 10 may, if desired, be utilized in conjunction with the refrigerated container shown in Figs. 1 to "I, inclusive.

The operation of the modified forms of my invention shown in Figs. 8, 9 and 10, will, of course,

be similar to that of the preferred form shown in Figs. 1 to 7, inclusive, except that it will be understood that the forms of the invention shownin Figs. 8 and 9 are adapted primarily as individual insulatedlockerdevices in locker storagepiants, rather than as shipping containers.

By having a locker storage plant provided with an individual food storage cabinet of the type shown and described, each subscriber may rent one or more of the cabinets as his particular the size of the central refrigerating unit and in its power operating costs may thereby be effected. Furthermore, the building housing the locker storage plant need not be heat insulated, and

this may be off-a more economical construction.

Due to the fact that the containers may, if desired, be located in a room kept at a moderate temperature, the subscribers may have access to their containers without the discomfort and danger to health entailed by entering a room maintained at a very low temperature.

The modification of the invention shown in Fig. 18 may, of course, be used as a shipping container, as well as a refrigerator for more gen- .eral uses.

It will be noted that in all of the constructions in which dry ice is used as the refrigerating medium, the resulting carbon dioxide is not permitted to co'me in contact with the contents of the container, but instead is conducted directly to the atmosphere. This is of considerable advantage when the container is used to transport certain foods which are'injuriously affected by being maintained in an atmosphere of carbon'dioxide 7 for an appreciable length of time.

While I have shown and described particular embodiments of my invention, it will be apparent to those skilled in the art that numerous varia-. tions and modifications thereof may be made without departing from the underlying principles of my invention; I therefore desire, by the following claims, to include within the scope of my invention all such similar containers whereby substantially the results of my invention are obtained by substantially the same means I claim.

I claim: v r

1'. In a refrigerated container for the shipment of frozen foods andthe like, the combina tion of a cabinet having heat insulating walls and two doors opening thereinto, an air-tight casing secured within said cabinet and having means for charging it with dry ice, means for maintaining the pressure within said casing at a super-atmospheric pressure to decrease the rate of evaporationof dry ice contained in said casing, a plurality of air circulating passageways having walls in heat conducting relationship with said casing, said passageways being accessible for cleaning and defrosting upon the opening of one of said doors.

2. The combination set forth in claim 1,'in which said passageways are formed directly beneath said casing, and have open ends for the circulation therethrough of air in said container.

' 3. In a portable refrigerated container for-the shipment and storage of frozen foods and the like, the combination of a'cabinet having heat insulated walls having vertically extended corrugations along the interior surface thereof to assure circulation of air in said cabinet around ing with dry ice, a conduit connecting the interior of said casing with the atmosphere, and a pressure controlling valve in said conduit operable to control the rate of evaporation-10f dry ice in said casing by maintaining the contents of said casing at a predetermined superatmospheric pressure.

5. In a portable refrigerated container for the shipment and storage offrozen foods and the like, the combination of a cabinet having heat insulated walls and a pair of doors opening therebetween said pipe and said casing.

6. In combinatioma cabinet having heatinsulating outer walls and having doors for obtaining access to the interior of the cabinet, a casing having a dividing wall separating said casing into an upper and lower compartment,

products closely packed therein, a pair of doors opening therei'nto, an air-tight casing secured within said cabinet and located at the top there of, means for charging said casing with dry ice, a conduit connecting the interior of said casing with the atmosphere, and a pressure controlling valve in said conduit operable to control the rate of evaporation of dry ice in said casing by maintaining the contents of said casing at a prede 'termined superatmospheric pressure.

4. In a portable refrigerated container 'for the shipment and storage of frozen foods and the like, the combination of a cabinet having heat insulated walls having projections on the interior thereof'to assure a' space for circulation of air between the cabinet'walls and closely packed packages contained within the cabinet, and a pair of doors opening into saidcabinet, an airtight casing secured within said cabinet and located at. the top thereof, means for charging said casmeans for cooling the interior of said-upper compartment, a liquid having a freezing point lower than that of water contained in said lower compartment, and means providing passageways along the vertical interior walls of said cabinet to permit the circulation of air around closely packed contents of said container toward and away from said casing.

7. In combination, a cabinet having heat insulating outer walls and having doors for obtaining access to the interior of said cabinet, a casing secured adjacent to the top within said cabinet, a coil surrounding said casing, a conduit connected to saidcoil extending adjacent the interior wall of said cabinet, means for circulating the refrigerating means throughsaid coil and conduit, and means providing passageways along the vertical interior walls of said cabinet to'permit the circulation of air around closely packed contents of Zsaid cabinet toward and away from said casing.

. LEONARD F. CLERC. 

